First host plant record and later instars of Pelolasia eusepus (Lepidoptera: Riodinidae) associated with Miconia calvescens (Melastomataceae), with the first report of parasitism by Tachinidae

Pelolasia eusepus (Hewitson, [1853]) is the most widely distributed species of the Neotropical genus Pelolasia Grishin, 2021 (Lepidoptera: Riodinidae), yet its biology remains virtually unknown. Here, the first host plant record for P. eusepus is provided, and its immature stages are documented, along with notes on its natural history. Larvae were collected feeding gregariously on Miconia calvescens DC. (Melastomataceae) in Ilhéus, Bahia, north-eastern Brazil, and reared under laboratory conditions. The morphology of the penultimate and last larval instars and the pupa is described, and aspects of larval behavior, pupation sites, and developmental duration are reported. Of 33 larvae collected, eight adults emerged, while most pupae were parasitized by dipterans, including two individuals of Houghia Coquillett, 1897 (Diptera: Tachinidae: Exoristinae). These findings reinforce the importance of Melastomataceae as host plants for Pelolasia species and expand the known herbivore fauna associated with M. calvescens, native to Brazil but highly invasive in several regions worldwide. This study provides baseline biological information for a widespread but poorly known Neotropical riodinid butterfly.